I can tell you another thing to watch that almost bit me... TWICE!
On the first few sections there is an example problem directly under the instructions ... I don't know why really. I honestly think it was to make sure you are paying attention.
Anyway I developed a habit during practice tests to double check my bubble placement against the number I was working when I answered things to avoid mistakes like this. So I never even read the #1 question and was looking for the #2 question. I didn't realize until I was done and had a few minutes to go back and look over. I went back and was like WTF? I don't remember this question for #1 and got myself lined out. Luckily I had put the example answer for #1 and then completely skipped the actual #1 and went to #2.
BUT...
If you managed to do this and not skip #1.. well obviously you can see how that would be a problem. Example answer for #1, #1 answer in the #2 spot and so forth.
They had those example problems on the first 3 sections if I remember correctly.
I did the same thing on the 2nd section but caught it much quicker.
I don't know why they have those examples they know we have all taken 10 bazillion tests using this format. I think it was on purpose to try and catch people not paying attention personally... Just like the stupid bubble on the back page that you have to fill in when you sign your name. You did fill in the bubble .... didn't you???
Oh yeah, I wore a watch.. no problems. Just be sure you don't have any alarms set or whatnot. The proctor for ours acted like it would cause a no score if it went off. I don't know how serious he was but I know it caused me to double check that all of mine were OFF.
Whoever mentioned being able to know where you should be according to how much time has gone by is right on the ball in my opinion. I checked my time after every 12th problem to be sure I was on target to atleast finish in time even if I wouldn't have extra time. (except the math because I was skipping so many I knew I would have plenty of time to do the ones I was sure of HAHAH)